Traditional interferometric fiber optic sensing systems utilize high sensitivity transducers within optical interferometers coupled with interferometric phase demodulation systems to generate high sensitivity, high linearity, low noise outputs. Recently, interest has been generated in backscatter systems that process scattered optical return from long lengths of optical fiber using a high speed interrogator to produce low sensitivity output that is scalar in nature (highly non-directional) but is extremely inexpensive to produce since the sensor array is simply a long tubed length of optical fiber.
Backscatter systems have some advantages over interferometrically interrogated fiber optics sensing systems, such as cost and reliability (e.g., due to lower parts count). However, such systems have some significant drawbacks including, for example, low sensitivity and output signal fading over time (e.g., leading to time periods of very low signal-to-noise, and reduced performance).
Thus, it would be desirable to provide improved fiber optic sensing systems overcoming deficiencies of the aforementioned systems.